Package org.snmp4j.agent.agentx.subagent

Class AgentXSharedMOTableSupport<R extends org.snmp4j.agent.mo.MOTableRow,A extends org.snmp4j.smi.Address>

java.lang.Object
org.snmp4j.agent.agentx.subagent.AgentXSharedMOTableSupport<R,A>
All Implemented Interfaces:
EventListener, org.snmp4j.agent.mo.MOTableRowListener<R>
public class AgentXSharedMOTableSupport<R extends org.snmp4j.agent.mo.MOTableRow,A extends org.snmp4j.smi.Address> extends Object implements org.snmp4j.agent.mo.MOTableRowListener<R>
The AgentXSharedMOTableSupport provides helper functions for shared table implementations to register rows and indexes at a master agent.
Version:
2.2
Author:
Frank Fock

  • Field Details

    • INDEX_MODE_ALLOCATE

      public static final int INDEX_MODE_ALLOCATE
      Allocate a specified index.
      See Also:

    • INDEX_MODE_ANY_INDEX

      public static final int INDEX_MODE_ANY_INDEX
      Allocate any (new or used) index and return it.
      See Also:

    • INDEX_MODE_NEW_INDEX

      public static final int INDEX_MODE_NEW_INDEX
      Allocate and return a new index (never used before).
      See Also:

    • indexRegistry

      protected SubAgentXIndexRegistry indexRegistry
      The index sub-agent registry.

  • Constructor Details

    • AgentXSharedMOTableSupport

      public AgentXSharedMOTableSupport(AgentX agentX, AgentXSession<A> session, org.snmp4j.smi.OctetString context)
      Creates a shared table support object for a AgentX connection, session, and context.
      Parameters:
      agentX - an AgentX connection.
      session - an AgentXSession session (does not need to be open at creation time).
      context - a context ("" by default).

    • AgentXSharedMOTableSupport

      public AgentXSharedMOTableSupport(AgentX agentX, AgentXSession<A> session, org.snmp4j.smi.OctetString context, byte priority, byte indexAllocationMode)
      Creates a shared table support object for a AgentX connection, session, and context.
      Parameters:
      agentX - an AgentX connection.
      session - an AgentXSession session (does not need to be open at creation time).
      context - a context ("" by default).
      priority - the registration priority used for this shared table support.
      indexAllocationMode - the index allocation mode to be used as default for this shared table.

  • Method Details

    • rowChanged

      public void rowChanged(org.snmp4j.agent.mo.MOTableRowEvent<R> event)
      Process shared table row events. If index mode is INDEX_MODE_ALLOCATE this method will do nothing if the associated AgentX session is closed. For other index modes, the event's veto status will be set to the AgentX error AgentXProtocol.AGENTX_NOT_OPEN.

      If the index OID of a created row has zero length then, depending on the current index mode, a new or any new index is allocated at the master agent.

      Specified by:
      rowChanged in interface org.snmp4j.agent.mo.MOTableRowListener<R extends org.snmp4j.agent.mo.MOTableRow>
      Parameters:
      event - a MOTableRowEvent indicating a row change in an AgentX shared table.

    • getEffectiveIndexMode

      protected byte getEffectiveIndexMode(org.snmp4j.agent.mo.MOTableRowEvent<R> event)
      Gets the effective index allocation mode for a table event.
      Parameters:
      event - the table event with the reference to the shared table.
      Returns:
      INDEX_MODE_ALLOCATE, INDEX_MODE_ANY_INDEX, and INDEX_MODE_NEW_INDEX.

    • getEffectivePriority

      protected byte getEffectivePriority(org.snmp4j.agent.mo.MOTableRowEvent<R> event)
      Gets the effective priority for a table event.
      Parameters:
      event - the table event with the reference to the shared table.
      Returns:
      the effective priority.

    • allocateIndex

      public int allocateIndex(org.snmp4j.smi.OctetString context, org.snmp4j.agent.mo.MOTableIndex indexDef, byte indexAllocationMode, org.snmp4j.smi.OID allocatedIndex)
      Allocate a new or any index at the master agent and return its value in allocateIndex. For the index strategies AgentXSharedMOTableSupport.IndexStrategy.firstSubIndexOnly and AgentXSharedMOTableSupport.IndexStrategy.anyNonAllocatedSubIndex a local index registry maintains a reference to all allocated index values. If an allocation fails, the index value is removed from the registry.
      Parameters:
      context - the context for which to allocate the index. Specify an empty OctetString for the default context.
      indexDef - the index definition with OID values for sub-index definitions.
      indexAllocationMode - one of AgentXProtocol.FLAG_ANY_INDEX, AgentXProtocol.FLAG_NEW_INDEX, or 0 (if index value is supplied by allocateIndex).
      allocatedIndex - the index value to allocate or if indexAllocationMode is not zero then an (arbitrary non-null OID) which returns the allocated new index value. If allocateIndex is an instance of AnyNewIndexOID or NewIndexOID the index value of the row will be replaced by a globally unique index value allocated by the master agent. The caller is responsible for changing the row's index in the table model of the shared table.
      Returns:
      AgentXProtocol.AGENTX_SUCCESS if the index could be allocated or an AgentX protocol error code if allocation failed and allocateIndex is not altered.

    • handleIndexAllocationError

      protected int handleIndexAllocationError(org.snmp4j.agent.mo.MOTableIndex indexDef, org.snmp4j.smi.OctetString context, org.snmp4j.smi.OID allocatedIndex, AgentXResponsePDU resp)
      Handle an index allocation error. By default, this method simply returns the AgentX error status from the master agent response. By overwriting this method, sub-classes may ignore such errors (for example, if using some of the "always..." index strategies.
      Parameters:
      indexDef - the index definition for the index whose sub-index allocation failed.
      context - the context of the allocation.
      allocatedIndex - the index OID of the sub-index that failed to allocate.
      resp - the AgentX reponse from the master agent.
      Returns:
      an AgentX error status or AgentXProtocol.AGENTX_SUCCESS to ignore the error.
      Since:
      2.1

    • deallocateIndex

      public int deallocateIndex(org.snmp4j.smi.OctetString context, org.snmp4j.agent.mo.MOTableIndex indexDef, org.snmp4j.smi.OID allocatedIndex)
      Deallocate an index at the master agent.
      Parameters:
      context - the context for which to allocate the index. Specify an empty OctetString for the default context.
      indexDef - the index definition with OID values for sub-index definitions.
      allocatedIndex - the index value of the previously allocated index.
      Returns:
      AgentXProtocol.AGENTX_SUCCESS if the index could be deallocated or an AgentX protocol error code if deallocation failed.

    • registerRow

      public int registerRow(org.snmp4j.agent.mo.MOTable<?,?,?> table, R row2Register)
      Register a row at the master.
      Parameters:
      table - the table owning the row.
      row2Register - the row to register.
      Returns:
      the AgentX status of the registration.

    • registerRow

      public int registerRow(org.snmp4j.agent.mo.MOTable<?,?,?> table, R row2Register, byte priority)
      Register the necessary regions for a table row.
      Parameters:
      table - the MOTable to register rows for.
      row2Register - the row to register.
      priority - the priority (default is 127). A smaller value takes precedence over larger values.
      Returns:
      the AgentX status of the registration.
      Since:
      2.1

    • unregisterRow

      public int unregisterRow(org.snmp4j.agent.mo.MOTable<?,?,?> table, R row2Unregister)
      Removes the region registration of a table row. the MOTable to register rows for.
      Parameters:
      table - the table to be modified.
      row2Unregister - the row to unregister.
      Returns:
      the AgentX status of the registration.

    • unregisterRow

      public int unregisterRow(org.snmp4j.agent.mo.MOTable<?,?,?> table, R row2Unregister, byte priority)
      Removes the region registration of a table row.
      Parameters:
      table - the MOTable to register rows for.
      row2Unregister - the row to unregister.
      priority - the priority (default is 127). A smaller value takes precedence over larger values.
      Returns:
      the AgentX status of the registration.
      Since:
      2.1

    • setPriority

      public void setPriority(byte priority)
      Sets the priority for the region registrations made by this table support.
      Parameters:
      priority - the priority (default is 127). A smaller value takes precedence over larger values.

    • setSession

      public void setSession(AgentXSession<A> session)
      Sets the AgentX session to be used for this shared table support.
      Parameters:
      session - an AgentXSession instance.

    • setIndexMode

      public void setIndexMode(byte indexMode)
      Sets the index mode to be used by this shared table support object. INDEX_MODE_ALLOCATE simply allocates index values at the master agent, whereas INDEX_MODE_ANY_INDEX fetches any currently unique index value from the master agent for a new row and INDEX_MODE_NEW_INDEX fetches a new index (never used before by the master).
      Parameters:
      indexMode - an index mode to be used for shared tables supported by this object.

    • setContext

      public void setContext(org.snmp4j.smi.OctetString context)

    • getPriority

      public byte getPriority()
      Gets the priority for the region registrations made by this table support.
      Returns:
      a priority.

    • getSession

      public AgentXSession<?> getSession()
      Gets the AgentX session used by this shared table support object.
      Returns:
      an AgentXSession instance or null if there is no connection/session established with the master agent.

    • getIndexMode

      public byte getIndexMode()
      Gets the index mode.
      Returns:
      INDEX_MODE_ALLOCATE, INDEX_MODE_ANY_INDEX, and INDEX_MODE_NEW_INDEX.

    • getContext

      public org.snmp4j.smi.OctetString getContext()
      Gets the context.
      Returns:
      the SNMPv3 context.

    • getAgentX

      public AgentX getAgentX()
      Gets the AgentX protocol.
      Returns:
      an AgentX instance.

    • getIndexStrategy

      public AgentXSharedMOTableSupport.IndexStrategy getIndexStrategy()
      Gets the index strategy of this shared table support.
      Returns:
      an AgentXSharedMOTableSupport.IndexStrategy instance.
      Since:
      2.1

    • setIndexStrategy

      public void setIndexStrategy(AgentXSharedMOTableSupport.IndexStrategy indexStrategy)
      Sets the index strategy for this shared table support. For most use cases the AgentXSharedMOTableSupport.IndexStrategy.firstSubIndexOnly strategy is recommended. With that strategy, only the first sub-index value will be allocated at the master agent if it has not yet been allocated by this table support (for any table). Unless you need to allocated sub-indexes by a multi-sub-index table, because there does not exists a shared table for the same session with that sub-index as first sub-index value, you should always use the AgentXSharedMOTableSupport.IndexStrategy.firstSubIndexOnly or AgentXSharedMOTableSupport.IndexStrategy.anyNonAllocatedSubIndex. The AgentXSharedMOTableSupport.IndexStrategy.anyNonAllocatedSubIndex should be used for a master and dependent table combination where the dependent table(s) extend the index of the master table by additional sub-indexes.
      Parameters:
      indexStrategy - the new index allocation/deallocation strategy.
      Since:
      2.1